Pedestrian level wind environment assessment around group of high-rise cross-shaped buildings: Effect of building shape, separation and orientation

Abstract

a b s t r a c tBlockage of air circulation caused by the mutual sheltering effect of high-rise buildings in built-up areas in dense cities causes various health-and comfort-related problems. The combined effect of neighborhood geometry (e.g., re-entrant corners, wind incident angle, passage angle, and building separation) on wind flow at the pedestrian level is an active field of research. This study investigates the influence of the wind incident angle and passage width on the wind flow characteristics at the re-entrant corners of cross-shaped high-rise buildings. This study also examines the influence of stagnant zones and wake regions on ventilation potential and wind comfort around the case study arrangements at various wind incident directions. An investigation was performed from 16 wind directions using the standard keε turbulence model with revised closure coefficients. A wind tunnel experiment was conducted to validate the results, which revealed that wind circulation at re-entrant corners was substantially affected by the building orientations and separation. The wind catchment effect within the re-entrant corners and the sheltering effect of buildings at various wind incident directions and building separations are also discussed. Unstable vortices were formed in oblique wind directions; these vortices facilitate contaminant dispersion and wind comfort at re-entrant corners and near buildings.

A review on the study of urban wind at the pedestrian level around buildings

“…Therefore CFD simulation results require verification and validation [40]. Zahid Iqbal et al [2] mentioned that the simulation results for PLW speed obtained by std. − k ε are also affected for different model closure coefficients.…”

“…Std. − k ε [2,44,[52][53][54][55][56][57][58] Pros: Computationally efficient and economically viable. Agreement with wind tunnel measurement of wind speed is within 10% for regions with high wind speed ratio (…”

“…But orientation and shape of buildings majorly helps to improve PLW climate. Several studies [2,53,56] propose the configuration with square central space with prevailing wind direction towards the windward opened side face offer better PLW environment. As this configuration can effectively contain the air flow movements.…”

“…Such wind conditions are persistent in Hong Kong, Tokyo and New Delhi [1]. Many causalities have been reported due to the accumulation of air-borne SARS virus (Severe Acute Respiratory Syndrome) because of low wind speed zone at a building site in Hong Kong [2]. So it is inevitable to assess wind condition for pedestrian level comfort in the view of low wind speed as well as strong winds near buildings corners.…”

Improving Residential Wind Environments by Understanding the Relationship between Building Arrangements and Outdoor Regional Ventilation

“…Yang et al [11] analyzed effect of standard and staggered layouts of roadside multi-floor buildings on the pollutants dispersion. Ying [31] and Iqbal [32] also compared the layout patterns of high-rise residential buildings. However, most of these studies perform CFD simulations by simply combining several individual buildings, without considering the effect of surrounding buildings.…”